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750 stroker motor

dirtdigger

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Stroker motor from PA showed up yesterday with big thanks to K2750tracy for getting the stuff and shipping it to me. Big kuddos to his shipping job in a wooden crate! Never gotten a motor shipped to me packed this well.
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Now on to the goods. F2 based motor, has a 74mm stroked crank, which I have never heard of but I measured it out last night. They used stock length Carillo rods with stroker 73mm Arias pistons along with a .9" spacer under the RC big block. Works out to 1234cc. Never seen a sohc built that big.
Big stroke but was hoping they used shorter rods instead of the stroker pistons...as you can see the pin is into the oil ring which can lead to oil usage, but I guess it was a drag only motor so it wasnt too terrible. Need to see if I can source some new rings as they have an odd combination of thicknesses of rings. Or will keep my eyes open for shorter rods.
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Biggest reason for wanting the motor was the RC block. 73mm and in good shape. Also has ported f2 head which I haven't looked at yet but will look at later. Also Mikuni carbs in with the parts, need to check them out as well.
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Thanks Digger, Everything inside the block looks to be in good condition. Is the trans undercut as the PO said? Big question is, is it worth what you paid And what you expected.
 
Yeah tranny is undercut. They did a lot of grinding and smoothing in the cases so it seemed they were pretty serious about their racing. It is definitely worth the money even if I dont run the crank etc, I will still run the block and head on something. Need to see what I can come up with for rings and see if it is feasable to build it. If not I will swap the block onto my current drag motor so I can get rid of a pesky oil leak it developed. Plus I like the RC stuff lol. Probably going to run the Mikunis on another bike too. Yeah I am happy with it.
 
Glad your happy with the parts, Good to know about the stuff in the lower end, makes me less worried about whats in the DOHC engine I have and that the PO didn't BS me.
 
Haven't looked at it much yet, not sure if this was the one they actually ran or not because it isn't very big really. I think it can be used, going to do some buffing on the journals to see how deep the pitting is, the 750 actually runs fairly wide cam bearing clearances and are not terribly picky on that clearance so you can have some scuffing and it really wont affect durability much. Kind of suprised to see the chambers on the head had not been opened up to match the piston dome...looks like there was very slight contact at some point on the pistons or possible carbon build up. See no contact on the head so I am not sure.
 
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